In my experience reflections MAY BE positive AND negative, absorption MAY BE also positive AND negative, diffusion MAY BE also positive AND negative....
The important acoustic factor is the RATIO between them and the location of their working focus centers...
The means to determine this ratio, in relation with my listening experiments, are related the time and timing factors in the room, the pressure zones levels distribution and the difference that makes in timing and relative velocity between reflected and direct wavesfronts and the way we can use and modify them, in a word the geography of the room and his acoustical content...
No general recipe can replace listening experiments and certainly not the general fact that some reflections can be bad...
By the way my amplifier and dac are between my speakers on my desk and my computer screen too ... I dont say it is ideal placement but i say that with mechanical isolation there is no problem i can detect myself...My speakers are relatively big enough to fill a room under 20 feet square...My room is 13 feet square... And the ratio between reflected back/front and lateral reflections play a determinant role in imaging and in listener envelopment/ sound source width ratio....Then if someone place a TV between the speakers we can compensate these reflections by acoustic control at another location anyway...this placement of the TV is traditionally described as bad because people dont know how to compensate this excess of reflection at this spot and how to use it positively...
All room is delicately organized acoustically in a unique fashion we must learn our room and recreate it to our liking...
For me my low cost system rival anything i ever listen to or is not so far behind in many cases and i did not use my 8 headphones anymore because after acoustic treatment and control their sound dont rival my speakers on any acoustic factor even the intimacy factor...
Thanks to acoustic/psycho-acoustic science...It is not the very good design of my pieces of gear that did this miracles for me, just basic acoustic...
People associate hi-fi with brand name , i associate hi-fi with acoustic now....
Something reflective between speakers? Thats about as bad as a TV between the speakers. Most think that absorption or diffusion works best.